Throttling process, thermodynamics

Third law of thermodynamics, 162-163 Throttling process, 77, 232-234, 291-292 Tie line, 365, 454-455 Triple point, 54, 61-62, 184-185 Turbine, 225-231 Tuibojet, 269-270 Two-phase systems, 180-183 Clapeyron equation for, 114-115 quality in, 183 See also Phase equilibria)... 

The supercritical solvent is expanded with the throttling valve (9) in order to remove the caffeine (separator 8) and to bring the solvent back to the liquid state (condenser 10). The gasrecycling (dry running) reciprocating compressor (7), the C02 and the co-solvent feed (2, 3 diaphragm pumps) represent variable process components if required. Heat exchangers (4) maintain the suitable thermodynamic conditions. 

An absence of phase and dynamic balance in the system makes it necessity to take into account process dynamics. This is the case for mixture motion in regions with rapidly varying external conditions, as, for instance, in throttles, heat exchangers, turbo-expanders, separators, settlers, absorbers, and other devices. Violation of thermodynamic and dynamic balance may cause intense nudeation of one of the phases (liquid or gaseous) with formation of drops and bubbles, and their further growth due to inter-phase mass exchange (condensation, evaporation) this process is accompanied by mutual interaction of drops, bubbles, and other formations, which results in their coagulation, coalescence, and breakup. 

Perform thermodynamic analysis on individual process units such as heat exchanger, turbines, pumps, compressors, and throttling valves. 

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